Project Summary (Core B) In the previous funding cycle, the Neuropathology Core (Core B) established a highly effective brain tissue banking system that greatly facilitates the success of research projects in this PPG. In the renewal proposal, Core B will continue its mission to provide high quality 2nd ? 3rd trimester, perinatal and early postnatal human brain tissues from the Autopsy Service in the Department of Pathology at UCSF for all the components of the PPG. In particular, Core B will focus on preparing tissues for single cell RNA-seq (scRNA-seq), single nucleus RNA-seq (snRNA-seq), RNAscope and ultrastructural analyses, which will prepare researchers and project leaders in this PPG to characterize the molecular and cellular mechanisms of cell lineages in the developing human brains. Core B will develop state-of-the-art molecular markers that will facilitate the discovery and characterizations of neuron-glia interactions during normal human brain development. Core B will provide full- time histopathology services that facilitate the progress among the research projects in this PPG as well as coordinate activities with the internal and external advisory committees. In essence, the aim of the Neuropathology Core is to function as a centralized facility where human brain tissues and advances in histopathology techniques can be utilized to provide support and integration of services for all investigators. The core director will work with the project leaders and make decisions regarding the use of core services. As an active member of the PPG, the core director will participate in weekly meetings regarding administrative and scientific matters such as research directions, requests for specific human tissues, data analyses, collaborations and presentations of data. The core director and co-director, in consultation with Dr. Alveraz-Buylla, Dr. Rowitch, Dr. Fancy, and Dr. Piao, will evaluate the specific needs and cost-effectiveness in order to maximize the service of Core B to each research project. The core director will ensure that quality control is provided at the highest level. Additional quality control will be achieved through the use of our internal and external advisory committees.